function s1_hello(){
  echo "hello,world!"
}
s1_hello

function s2_tell_who_i_am(){
  echo "Enter you name:"
  read user_name
  echo "user name is $user_name"
}
s2_tell_who_i_am

function s3_which_distro_do_i_use(){
  NAME="Beta Linux"
  echo $NAME
}
s3_which_distro_do_i_use

function s4_view_my_cpu_arch(){
  uname -m
}
s4_view_my_cpu_arch

function s5_show_first_scsi_disk_size(){
  lsblk -l|\grep disk|\grep'^sda'|awk'{print $4}'
}
s5_show_first_scsi_disk_size

function s6_show_main_memory_size_in_megabytes(){
  free -m|grep "Mem:"|awk '{print $2}'
}
s6_show_main_memory_size_in_megabytes

